And it’s that moment of the year again, when we are buzzing with anticipation for the next mini maker faire. This year the date has shifted to 16-17 September, when the schools are just opening and it’s time to look for inspiration for new projects.

The location sis always the ICTP campus, where we will be laying out tables, gazebo, platforms and chairs to have fun and play with technology and innovation.

There is still time to apply as a maker, we are searching for any kind of crazy innovative project, weather it’s tech related or not.

And if you want to really be part of the faire, but feel you are not (yet!) confident enough to come share your ideas, you can help us out with the organisation. We need volunteers for a hundred different jobs: helping the public, assisting the makers, setting up tables and chairs…

As a maker, a volunteer or a visitor, do come and feel the excitement!!

New task: make stamps for an activity with children! We need 10 stamps to use on a “passport” for the children that will come every day for different activities. Just the right occasion to use the flexible PLA we bought quite a while ago, because stamps must be rubbery So, there are many ways to make a stamp, but having no 3d modelling abilities I had to find quite a complex workaround and here we are.

1: the actual design for the stamps was made with a graphical software and exported as a PNG.

3: Netfabb to the rescue!! Just fire it up and open the file, then you can save it as an Stl. If you forgot to do it, you can mirror the design so the letters don’t come out written backwards (yes, we’ve done it!)

4: now we have to add the back of the stamp, you could have done it before maybe, but we were not certain how it would come out when extruding it so we decided to add it now. I use Tinkercad, just import your stl, design a flat cylinder and stick it on. Obviously this step can be greatly improved, feel free to add any ideas in the comments!

5: and we finally have a printable stl file!! We chose to print it with Ultimaker’s Flexible PLAI strangely had no problems printing with it, obviously I drastically changed the speed (10mm/sec) but when in a hurry to finish a piece I increased it I had no difficulties. I wanted to exclude retraction but left it by mistake and had no problems.

The first experiment was with 200° and the details peeled off, so we tried with 235° and it sticks wonderfully. Using these settings we found out that it kept the finer details, and when using it with ink it looked much better.

Maybe slightly melting the last layer (touching a heated surface) would improve the final effect making all the lines disappear.

The new version of Cura (14.07) has finally decided to add all Printrbot’s to the initial setup wizard, so when you install it for the first time it just asks which printer you have, and configures everything accordingly.

Though this already made my day (as I was having horrible problems connecting my Kubuntu based laptops with the printrbots) I still had the problem of how to manually change filament, move the print head and so on, as my printrbots don’t have controllers like the ultimaker.

But searching the web I found you can very easily add a Pronterface UI to Cura, and happily change filament, check temperatures and so on

Just hop on File-Preferences and choose the Printing window type.

Next time you hit the “Print with USB” you will have a cute little Pronterface window (ooooh, old memories!)

Just another note: In the initial settings for Printerbot simple, maker kit 2014 the nozzle is set at 0.4mm, check if it really is so as the size has been changed various times. I found this handy note on the Printrbot forum

The Getting Started Guide says that all Printrbots currently ship with 0.4mm nozzles.The convention for identifying nozzles is based on notches (or “rings”) cut into the sides (vertices) of the hexagonal brass “nut”.No notch = 0.5mm1 notch = 0.4mm2 notches = 0.35mm

A huge thanks to my friend Gregor that poked me asking how come I wasn’t posting anymore. The reason is simple, I changed job and while I still work with 3D printing I have also other things to carry on so blogging just slipped away. But I’ll try to update sometimes, I have a huge amount of things to show and have been working on many exciting projects.

Today for instance I have to print out some scans we made saturday of kids that had their birthday on the same day as our Science museum, right now Giacomo is on the printbead, then it’s the turn of Marcello, Savita and Sara

After quite a long time I had to print out something with Cura, and all my prints turned out horribly: thin walls, no top, no infill. I just couldn’t remember what I printed the last time with that software and how I had changed the settings. And unfortunately Cura has n’t got a “revert to default settings” option.

I checked the obvious menu choices: the infill was correct, I had a top thickness and in the expert settings I had already checked Solid infill top and bottom. But the prints continued to turn out empty and flimsy, even though I had installed the new version of Cura hoping it started out with default settings (no, it doesn’t, yuck).

And then I finally spotted the Spiralize option. Previously I though it was active only when choosing a 0 infill but I found out it overrides all other menu options.

So just beware: if your prints turn out strangely empty and without the top, check in the expert settings if the spiralize option is highlighted. Sometimes the solution is just too easy to be easily spotted

PS: I just saw that in the version 14.01 of Cura (and maybe also in previous ones) there is a “reset profile to default” so if all goes wrong, this is certainly something to try out

Change of topics today, because I have a new job (yeah!) that requires me to work much more with arduino than with 3d printers. So I’ve been scouring the web in search of help for some of the most strange topics and I had my share of problems when trying to program the small lilytiny I bought some while ago.

I chose a Lilytwinkle, that is identical to the Lilytiny but just comes preprogrammed with some cute effects so you can choose on which pin to attach your led depending on the light effect you want to achieve.

But my LilyTwinkle turned out to be a non programmed LilyTiny, so I had to program the damn little thing…. And the problems started because I found no real guide on how to do it. So as a reminder for myself, and to help out any other lost soul trying to program these small cute little boards, here’s my guide.

I use a Mac, so I don’t need to add any drivers but Windows asks for other stuff and you can find info about it on the High-Low Tech page at MIT Media Lab. The webpage is not working anymore (yuck) but the internet archive will help us out luckily.

Now it’s time to have a look at our Arduino, because we need to add support for these teeny weeny boards that are not included by default. You can download it from GitHub, and it’s the attiny file. Be careful that if you have already installed the Gemma and Trinket boards they installed with the same name, so be careful and don’t mess up the folders. You now will have a nice new set of boards from which to choose from, and I found choosing ATtiny85 (internal 1 MH clock) works for me. If someone has a different setup that works better please tell me, I have to admit I chose trial and error system

And it’s time to write the code down, and start playing with the various effects. Map the pins like this (I know it’s obvious, but non the less someone out there will appreciate the obvious steps)

// the loop routine runs over and over again forever:void loop() { digitalWrite(led0, HIGH); // turn the LED on (HIGH is the voltage level) delay(500); // wait for a second digitalWrite(led0, LOW); // turn the LED off by making the voltage LOW delay(500);

……

}

And upload it! Choose the right board, don’t fuss with the serial port and check to have in the Programmer “USBtinyISP”. Now stab the small board being careful to align the contacts in the right direction (check the picture!) and while stabbing it upload the sketch. If it gives you an error try a couple of times because sometimes the connection is not that perfect, but be stubborn and you will end up with your small lilyTiny doing just what you asked her to do.